Ultimate DIY Water Filter! This Homemade Water Purifier is extremely effective and super easy to make. The “2 Stage” design purifies almost all water sources to 99.999%. Starts to produce clean/clear (super hot) water within 20 seconds! uses no electricity. great to have in a SHTF/Emergency situation or for everyday use. *also doubles as a water heater and stove burner!. you can cook on top of the coil at the same time the water is heating/purifing! water purifier, water heater and stove all in one! *and with the exception of the activated carbon and the copper coil, the filter is made almost entirely out of “free stuff” (recycled/reused metal cans, plastic bottle, glass jar – along with sand and gravel). note that the “1st stage” of the filter (activated carbon part) removes predominantly the chemical impurities (along with bad taste/color/odor/sediment). while the “2nd stage” (heated coil) predominantly removes the biological contaminants (parasites/bacteria/viruses etc…) when used together they’re extremely effective as a filtering system. should purify almost all water sources. note – one of the few things it won’t remove is salt from salt water and certain minerals. of interest: total length of copper tubing is 10 ft. tubing is 1/4″. a crumpled up piece of coffee filter paper can be used in place of the cotton balls. i was able to purifiy 12oz of water every 3 mins or so (about 1/2 gallon every 15 mins). it uses about 25 cents worth of 70% isopropyl alcohol to purify a gallon. (i imagine in a pinch, since the can that holds the copper coil is very similar to a tin can stove, you could use small sticks, twigs and leaves as a fuel source instead of the alcohol). Of note: it only “steams up” for a few seconds every few minutes or so. most of the time the flow of escaping water vapor/steam is light and barely visible.